Giant sunfish washes up on beach in South Australia (Picture)

A group of friends on a fishing trip to the mouth of the Murray River in South Australia has accidentally stumbled across one of the world’s biggest fish.

Their find was the body of a sunfish, 2.5m long and weighing hundreds of kilograms.

From a distance they thought it was a big rock but as they moved closer they realised it was a fish.

Fish expert Ralph Forster from the South Australian Museum identified this sunfish for Kids News as an example of the mola mola species of sunfish, which is extremely rare where it was found.

The friends found the sunfish in the shallows north of Tea Tree Crossing in the Coorong on Saturday afternoon. The Coorong is a rich ecosystem* of wetlands and lagoons between the Murray River and the Great Australian Bight, which is part of the Southern Ocean.

Mr Forster said it was not known how it died, as from the photographs it looked in good condition. Mola mola like eating jellyfish and he said they have been known to mistake plastic bags for jellyfish, which is a possible cause of death.

SUNFISH

Sunfish are among the world’s heaviest fish, weighing between 250kg and 1000kg.

They are seen in tropical and temperate* waters around the world.

They love to sunbathe and spend hours each day close to the surface of the water.

The family of species is considered as vulnerable* to extinction in the wild but is also considered a delicacy* to eat in countries including Korea, Japan and Taiwan.